Lost backpacker drank lens fluid and urine

A young British backpacker found alive after three nights lost in the Queensland outback survived by drinking contact lens fluid and his own urine, his mother has revealed.

Claire Derry said her 18-year-old son Sam Derry-Woodhead had lost 15 kilograms during his ordeal in searing heat on a remote property 130 kilometres from Longreach.

Sam, who went missing on Tuesday afternoon from Upshot Station, where he had spent about 10 days working as a jackaroo as part of his gap year, was found sunburnt and dehydrated on Friday.

"He tried drinking his own urine and that was pretty revolting experience and he wasn’t able to cope much with that," Ms Derry said.

"So he drank tiny sips of the contact lens fluid he had with him and that saved him. He lost 15 kilograms though.”

A group of 50 people had searched an area of about 500 square kilometres of ‘‘extremely harsh terrain’’ in temperatures reaching 39 degrees, police said.

Conditions were so bad, two State Emergency Service volunteers taking part in the search had to be taken to hospital suffering heatstroke.

Waiting to board a flight to Longreach at Brisbane Airport this morning to be reunited with her son, a smiling Ms Derry told of her ‘‘absolute joy’’ at finding out Sam was alive.

She had been en route to Brisbane from the UK when she was given the news.

"One of the airline staff came up to me and he was smiling...he handed me this piece of paper saying Sam was found alive and well.

‘‘I screamed and hugged him and hugged the rest of the crew and they brought me champagne to celebrate...it’s just amazing, absolutely amazing," she said.

Ms Derry said she had feared the worst.

"It really hit me at Heathrow. I was reading the press (coverage) about snakes and how most people don't survive the outback," she said. ''I was feeling desperate.”

She brought a friend with her for moral support.

“Not knowing what I was going to find, what I was going to have to deal with when I got here...I thought I need my dear friend if I go in there and it’s bad news.”

Ms Derry spoke to Sam over the phone this morning, telling her of how the rescue team had joked with him in an attempt to make him smile.

“When the two guys in the helicopter arrived, he said ‘They took the p--- out of me Mum. They said they normally find people out here with their eyes pecked out’...and he said he had to laugh,” Ms Derry said.

“Nothing was not done to help him and we’re incredibly lucky.”

She said Sam sounded weak and had not been able to keep any food down but was grateful to Queensland Police and search volunteers.

“All he could say was: ‘Mum, just thank these wonderful people. I’ve loved Australia from the minute I arrived here...these people are extraordinary’.”

Ms Derry was flying to Longreach to be reunited with her son at Longreach Hospital. Sam had been released from the hospital on Sunday, the ABC reported.

“I am desperate to see him. When I see him it’ll be a mixture of wanting to hug him and to tell him off for what he’s put us all through!”

She credited his survival to his fitness and previous training at the Royal Military Academy Sandhurst.

“Sam is physically incredibly fit; that was something I clung on to. He wants to go into the Royal Marines or Army,” she said.

“He’d not long ago been on an appropriateness course for Sandhurst and on that course they’d done a command post and rescue (training) and so I knew he had a lot of knowledge to draw on.”

Sam’s father and two sisters, who stayed behind in the UK, had been advised of the news and were celebrating back in England.

Sister Rebecca Woodhead wrote on her Facebook page: “It has been a very long couple of days, we have just finished with all the press so I'm going to go to bed for the first time since this started.

“I cannot thank everyone enough, if it weren't for all the help we've had, we might not have got the result we have.”